The Foreshore

Hard rocky shores, sandy beaches and intertidal mudflats have all been used by humans over generations. Coasts themselves have experienced great change in the form of sea levels and erosion over millennia. Evidence for changing sea levels is apparent in the fine examples of submerged 'forests' and old land surfaces encountered in the intertidal zone. The remains of tree stumps, roots and branches have been recorded at a number of locations in Strangford Lough, mainly in the north in the Comber estuary and Greyabbey Bay. Wood identification has shown most of the remains to be oak and Scots pine. A number of these deposits have been radiocarbon dated to c. 6500-7000BC.

Extensive wooden fish traps were established in the early medieval period in Greyabbey Bay. The traps are generally located on the tidal channels, some of which have a freshwater component, which would have provided nutrients for feeding fish. All of the fish traps are ebb weirs, intended to catch fish drifting down with the falling tide. These were replaced in stone by the Anglo-Normans in the 13th century. They range from 50-200 metres in length.

A more recent use of the foreshore has been for its seaweed, whether for fertilizer, foodstuff or kelp. In the 18th century the production of kelp (the commercial name for the burned ashes of seaweed) as a source of soda became a very important activity around the Irish shoreline. As an alkali, it was in great demand for glass-making, soap-making and as an agent in bleaching linen. The remains of kelp kilns are found around our coasts, but on the sandy foreshores of Carlingford and Strangford Loughs, boulders were artificially placed to encourage colonisation and so produce a crop. These features are known as kelp grids because of the regular spacing of the boulders.

Rocky foreshores, often being in dynamic, high energy areas, have fewer surviving structures but nevertheless impressive archaeology can still be present, such as the saltworks in Ballycastle. Over the space of three centuries production of salt was carried on by extracting it from seawater. The channels cut into the foreshore to access settling chambers can still be seen in the Fair Head area.